Kahne and Busch were racing for the lead on the second lap after a lap-332 restart when Busch suddenly went straight into a corner, slid up the track and sent Kahne's No. 5 car spinning.

It was unclear whether the two made actual contact, but Kahne said it didn't matter - the air pushed the car around even if they didn't touch, he said.

"I could see him (coming up the track), and I was like, 'Oh shoot, oh shoot!'" Kahne said. "Then the car moved and it spun out. So I don't know if he touched me or what, but the car's angle into the corner ... if he had just entered normal like he did the whole race, there'd have been no issues and I'd have been leading off (Turn) 2.

"He just didn't want that to happen, so he blew Turn 1."

Kahne said Busch "caused that whole deal ... with mind fade." He said it was the third time this year Busch has ruined his race, referring to two crashes in the restrictor-plate races at Daytona and Talladega (Busch called Kahne just last week to apologize for the latter).

Busch did not comment after finishing a disappointing sixth despite leading a race-high 265 laps. He got out of his car and walked straight into the No. 18 team hauler with his helmet still on.

When he emerged in street clothes a few minutes later, Busch made a hurried exit toward the driver motorhome lot, not saying a word as reporters trailed him and asked questions in a futile attempt for comment.

Crew chief Dave Rogers said Busch ran over something on the track and had a right-rear tire going flat at the end of the race, leading to the drop in positions.

Regarding Kahne, Rogers said his driver "was pretty tore up" about the incident.

"This is the third time we've been involved in an incident with Kasey," Rogers said. "All of us over here have a ton of respect for that program and Kyle thinks the world of Kasey Kahne. ... He was really somber and disappointed it happened. Unfortunately, it's part of this sport."

But Kahne speculated Busch couldn't stand the thought of losing the race on a restart after dominating all night long.

"I was the first car that raced him all night on the first couple laps (after a restart), and I did it the restart before, too," Kahne said. "That (second) one I could stay under him, I drove under him getting into (Turn) 3 and I had a preferred line getting into (Turn) 1 and he blew his entry.

"I think he just lost his head when someone else had some speed, too."

Asked if the incident could be attributed to typical Darlington racing, Kahne bristled.

"That wasn't Darlington!" he said. "Lots of things happen at Darlington, but the way he entered that corner, that was not Darlington. That was a mistake on his part."